The present invention relates to reminder apparatus for reminding the user as to a certain existing condition. Illustrative applications of the invention, as described below, are to remind the user whether and when he or she has locked a particular lock, and whether he or she has inadvertently moved greater than a predetermined distance from an unlocked door or another device to be secured by the user, such as a portable object being guarded by the user.
People frequently forget whether or not they have properly locked a door or similar device. This can be very troubling and may even require the person to return to see whether or not he or she actually did lock the door. In addition, a person may intentionally leave a door unlocked when the person is in the immediate vicinity, intending to lock the door should he or she move away from the immediate vicinity, but forgets to do so. Further, persons sometimes carrying portable objects, such as a briefcase containing valuables, may inadvertently wander away from the object.
An object of the present invention is to provide reminder apparatus for any of the above applications. A particular object of the invention is to provide reminder apparatus which enables the user to determine the time and nature of the last operation in which a key was used with respect to a lock, i.e., whether the key opened the lock or closed it. Another object of the invention is to provide reminder apparatus which provides an audible signal should the user move away a predetermined distance from a door while the door is not locked. A still further object of the invention is to provide reminder apparatus which produces an audible signal should a user be separated, voluntarily or involuntarily, from an object, such as a briefcase, guarded by the user.